1. A letter that/which is written in pencil is difficult to read. (主语)

12.(★★★★★)David gets up early and takes a walk in the morning, ______ is usual with him.

　　 A. as B. that C. what D. such

11.(★★★★★)I’ll never forget the days ________ I lived in the country with the farmers, ________ has a great effect on my life.

　　 A. that; which B. when; which C. which; that D. when; who

10.(★★★★)Helen is much more kind to her youngest child than to the others, ________ of course, makes the others unhappy.

　　 A. who B. which C. she D. that

9.(★★★★)That passenger was very impolite to the conductor, ________of course, made things even worse.

　　 A. who B. whom C. what D. which

8.(★★★★)Beijing government puts more than 700 million yuan to increase its green space this year, ________ doubles the money provided last year.

　　 A. as B. while C. that D. which

7.(★★★★)Another unmanned spacecraft“ShenzhouⅡ”,________China greets the 21st century, marks new progress in the century’s space program.

　　 A. for which B. from which C. in which D. with which

6.(★★★★★)Is there a shop around ________ I can get a pack of cigarette?

　　 A. which B. where C. that D. what

5.(★★★★)“Who Moved My Chinese?”,________is a best-selling book, is written by Spencer Johnson.

　　 A. which B. that C. it D. what

4.(★★★★)I’d like a car ________front lights are big and round.

　　 A. which B. that C. whose D. what